docs-files-api: a script that prints usage keeps its manual in HELP

Refines the program-script exception: when the script prints its usage,
the manual is a HELP string constant under a one-line @file (JS has no
docstrings), not a comment copied into code or re-read from source.

Generated-by: Claude Opus 5.5

docs-files-api/SKILL.md

@@ -20,11 +20,14 @@ JSDoc placement rules (from the
   above the declaration shows nowhere. `//` is for implementation notes
   inside a body: the *why* of a non-obvious line, next to that line.
 - **Exception: program scripts** (run directly: a shebang, or
-  `import.meta.main`). The `@file` comment is the script's manual: a
-  one-line purpose, a usage synopsis, the arguments, and what it writes
-  or prints. People open a script to learn how to run it, and its `main`
-  has no call sites for JSDoc to show at. Helpers inside still get their
-  own JSDoc.
+  `import.meta.main`). The manual goes at the top: a one-line purpose, a
+  usage synopsis, the arguments, and what it writes or prints. People
+  open a script to learn how to run it, and its `main` has no call sites
+  for JSDoc to show at. If the script prints its usage, make the manual a
+  `HELP` string constant right under a one-line `@file` (JavaScript has
+  no docstrings; a string literal is the honest equivalent) rather than
+  copying it or reading the script's own source. Helpers inside still get
+  their own JSDoc.
 - **External design constraints:** If a module is constrained by external
   contracts, standards, or off-repo design docs, add a short JSDoc note with a
   `@see` link to the authoritative source at the relevant entry point(s).